[PATCH 2/2] crypto: aead,cipher - zeroize key buffer after use

From: Hailey Mothershead
Date: Thu Apr 11 2024 - 19:52:52 EST


I.G 9.7.B for FIPS 140-3 specifies that variables temporarily holding
cryptographic information should be zeroized once they are no longer
needed. Accomplish this by using kfree_sensitive for buffers that
previously held the private key.

Signed-off-by: Hailey Mothershead <hailmo@xxxxxxxxxx>
---
crypto/aead.c | 2 +-
crypto/cipher.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/crypto/aead.c b/crypto/aead.c
index 16991095270d..2592d5375de5 100644
--- a/crypto/aead.c
+++ b/crypto/aead.c
@@ -36,7 +36,7 @@ static int setkey_unaligned(struct crypto_aead *tfm, const u8 *key,
memcpy(alignbuffer, key, keylen);
ret = crypto_aead_alg(tfm)->setkey(tfm, alignbuffer, keylen);
memset(alignbuffer, 0, keylen);
- kfree(buffer);
+ kfree_sensitive(buffer);
return ret;
}

diff --git a/crypto/cipher.c b/crypto/cipher.c
index b47141ed4a9f..efb87fa417e7 100644
--- a/crypto/cipher.c
+++ b/crypto/cipher.c
@@ -35,7 +35,7 @@ static int setkey_unaligned(struct crypto_cipher *tfm, const u8 *key,
memcpy(alignbuffer, key, keylen);
ret = cia->cia_setkey(crypto_cipher_tfm(tfm), alignbuffer, keylen);
memset(alignbuffer, 0, keylen);
- kfree(buffer);
+ kfree_sensitive(buffer);
return ret;

}
--
2.40.1